The present invention relates to an automatically controlled exposure indicating device for a camera having a multi-exposure control system and more particularly, to an exposure indicating device in a multi-exposure control system for a camera. The diaphram is stopped down from its fully open condition to measure the light rays reflected from the photographic objects and which passes through the objective lens and using a shutter speed preselected as a standard, automatically controls the diaphragm aperture to obtain a proper exposure. The apparatus carries out automatic exposure time control in accordance with the intensity of scene light which passes through the controlled diaphragm aperture. The apparatus also carries out automatic exposure control to provide a proper exposure using a diaphragm aperture preadjusted as a standard. Additionally, where the shutter speed is used as a standard when a diaphragm aperture of proper exposure cannot be obtained, automatic exposure time control is carried out by turning the diaphragm either to the fully open or the smallest aperture.
In the prior art, such a diaphragm automatic control camera is well known that uses a preselected shutter speed as a standard and measures the lightness of scene light from objects to be photographed which light passes through the objective lens and the diaphragm to obtain a proper exposure while stopping down the diaphragm aperture from its fully open condition. And a shutter speed automatic control camera is also well known, wherein by setting the diaphragm aperture beforehand the shutter speed is automatically controlled in accordance with the lightness of objects which pass through the objective lens and the diaphragm, and the shutter speed can be controlled so as to obtain a proper exposure. In such control system cameras either the shutter speed or the diaphragm aperture is controlled. Therefore, an indication of the controlled shutter speed or controlled diaphragm aperture can be done easily by making use of a meter or the like.
In such cameras, however, it is impossible to optionally select the shutter speed control or the diaphragm aperture control in compliance with the intention of an operator. In addition, in an automatic exposure control camera of such a type that automatically controls the diaphragm aperture by a preselected shutter speed, depending upon the lightness of objects to be photographed there sometimes occurs a case where even though the diaphragm aperture is adjusted to the smallest aperture for the preselected shutter speed, an overexposure may result. Also, there occurs another case where even though the diaphragm aperture is kept in its fully open condition, an underexposure may result, and thus controlling the diaphragm aperture for obtaining a proper exposure may become impossible.
Whereas, the assignee of the present application has proposed a camera of a multi-exposure control system in which the exposure control of both such systems is enabled, and the drawbacks mentioned above are removed. (U.S. Ser. No. 486,427, filed July 8, 1974.)
In such a multi-exposure control system camera, when it is intended to indicate an automatically controlled exposure, the exposure indicating device thereof becomes very complicated and expensive to manufacture, and accordingly difficult to adopt in a camera.